1. Field of the Invention
The present invention relates to a car interior part with an air bag cover portion such as an instrument panel, a door trim, a seat back or the like to which an air bag device is to be connected.
The present application is based on Japanese Patent Applications No. Hei. 10-363439 and 11-277704, which are incorporated herein by reference.
2. Description of the Related Art
In this specification, description will be given below mainly of an instrument panel but, of course, the invention is not limited to the instrument panel.
Also, in this specification, the front and rear as well as the right and left of a car interior part (instrument panel), unless otherwise specified, respectively correspond to the front and rear as well as the right and left of a car when the car interior part (instrument panel) is actually mounted in the car.
As a car interior part of this type, for example, in the case of an instrument panel 112 which has such a basic curved section as shown in FIG. 1, there is provided the following structure.
That is, the instrument panel 112 comprises a main body portion 114 and a cover portion 116 for connection to an air bag device, while the main body portion 114 and cover portion 116 are formed in an integrally united body in such a manner that the surface sides thereof are substantially flush with each other and, in the periphery of the back surface of the cover portion 116, there are provided two angular-shaped mounting walls 118a and 118b which can be connected to an air bag device. Reference character 120 designates a design seat which is insert molded for enhancement of the design of the instrument panel 112.
Now, the present instrument panel 112 is molded using a metal mold which, as shown in FIG. 1, is composed of a movable mold 122 and a fixed mold 124. And, the metal mold is opened in a direction intersecting at right angles to the maximum bulged portion of the curved section of the main body portion 114 in order not to produce any undercut in the curved section of the main body portion 114. As a result, the front and rear mounting walls 118a and 118b, which are formed so as to be substantially upright with respect to the upper surface of the instrument panel 112, produce an undercut which crosses a mold releasing direction (shown by an arrow mark in FIG. 1).
This makes it necessary to provide a first slide core 126 and a second slide core 128 in the releasing direction of the front and rear mounting walls 118a and 118b, with the result that the structure of the metal mold is complicated.
To solve this problem, as disclosed in Japanese Patent Publication No. Hei. 9-156444, there can be employed a structure in which, out of the front and rear mounting walls 118a and 118b, one mounting wall (rear mounting wall) is formed in the same direction as the mold releasing direction. However, in this structure, as set forth in the above-cited publication, it is necessary to provide, in an air bag device (air bag case), a mounting bracket (mounting member) which projects in a direction parallel to the mounting end portion of the rear mounting wall, that is, in the mold removing direction.
The present invention aims at eliminating the drawbacks found in the above-mentioned conventional car interior part with an air bag cover portion. Accordingly, it is an object of the invention to provide a car interior part with an air bag cover portion which not only can simplify the structure of a metal mold but also eliminates the need to provide in an air bag device a mounting member that projects in a mold releasing direction.
The present inventors have carefully studied the structure of the conventional car interior part for connection of an air bag device thereto and have found that, in order to solve the above-mentioned problems found in the conventional car interior part, at least one of the front and rear mounting walls of the mounting wall may be formed in the same direction as the mold releasing direction of the main body portion of the car interior part, and there may be formed an integral hinge portion in the portion of the mounting wall that is situated upwardly of the mounting portion of the mounting wall, whereby the mounting portion of the mounting wall can be mounted onto the air bag device while it is folded at the integral hinge portion thereof. Thus, the present inventors have successfully developed a car interior part with an air bag cover portion which has the following structure.
That is, according to the present invention, there is provided a car interior part designed for connection of an air bag device thereto. The car interior part comprises: a main body portion; a cover portion formed in the main body portion to thereby cover an air bag device; and a mounting wall formed in at least a part of a periphery of a back surface of the cover portion, to which the air bag device is connected. A mold releasing direction of the main body portion is set in a direction to cross a developing direction of an air bag of the air bag device. The mounting wall includes a front mounting wall and a rear mounting wall, and at least one of the front and rear mounting walls is formed so as to be extend in the same direction as the mold releasing direction of the main body portion. Further, at least one of the front and rear mounting walls has an integral hinge portion situated at a position upward of a mounting portion to which the air bag device is fixed while one of the front and rear mounting walls is folded at the integral hinge portion.
Preferably, the main body portion and the cover portion are integrally molded so that their respective surfaces sides are substantially flush with each other.
Further, the rear mounting wall has the integral hinge portion, and the car interior part further includes a plurality of reinforcing ribs, being disposed in parallel to the mold releasing direction of the main body portion. Preferably, a front end edge of each of the reinforcing ribs extends from the position of the integral hinge portion of the rear mounting wall in parallel to the front mounting wall.
Thanks to the above-mentioned structure, the car interior part with an air bag cover portion according to the invention can provide the following operation and effects.
That is, since at least one of the front and rear mounting walls is or are formed in the same direction as the mold releasing direction of the car interior part main body portion, there is eliminated the need for provision of one or both of the two slide cores that have been conventionally disposed on the mold releasing side of the rear mounting wall, which not only can simplify the structure of the metal mold but also can eliminate the need to provide an extra mounting member such as a mounting bracket or the like in the air bag device.
By the way, when the rear mounting wall is formed in the same direction as the mold releasing direction of the car interior part main body portion, since the rear mounting wall is reinforced by the reinforcing ribs, there is no possibility that there can arise a problem as to the strength of the rear mounting wall; and, if the surfaces of the respective reinforcing ribs including the rear ends thereof are formed so as to extend in parallel to the front mounting wall, then there is no fear that, when the air bag device is actuated, the air bag can get into a gap formed between the rear mounting wall and the back surface of the cover portion, which makes it possible to stabilize the developing property (inflatability) of the air bag.
Accordingly, it is possible to provide a car interior part with an air bag cover portion which-can be molded by a metal mold having a simple structure, which in turn can enhance the productivity of the car interior part.
Features and advantages of the invention will be evident from the following detailed description of the preferred embodiments described in conjunction with the attached drawings.